The present disclosure relates to image processing apparatuses and image processing methods, and particularly relates to an image processing apparatus and an image processing method which are capable of reducing a capacity for storing encoded data obtained by encoding images.
In recent years, in a field of a pathological diagnosis such as so-called cytoscreening and a tissue diagnosis, a digital pathological diagnosis has been performed using a virtual microscope.
The virtual microscope is an apparatus including a microscope device capable of obtaining image data and a computer which processes the image data. The virtual microscope captures an entire slide glass on which a sample (specimen) is placed and stores a microscopic image of the sample as a digital image.
By this, higher-level microscopic observation may be performed by appropriately performing image processing on the microscopic image of the sample and displaying the processed image on a display of a personal computer, for example, when compared with a case where a normal microscope is used for the observation of the specimen. For example, the image processing may be performed on the microscopic image so that the specimen is clearly viewed. Furthermore, a portion of the microscopic image may be enlarged for display, for example. Moreover, microscopic observation through the Internet may be performed.
In general, specimens used in a pathological diagnosis such as cytoscreening and a tissue diagnosis have thicknesses of themselves. Therefore, data of an image (Z-stack image) obtained by capturing such a specimen from a plurality of focus planes should be obtained to obtain a 3D structure of the specimen.
Note that, since a large capacity is used for uncompressed image data, it is difficult to store and manage the uncompressed image data. Therefore, in the Digital Imaging and Communication in Medicine (DICOM) standard, the JPEG (Joint Photographic Experts Group) is employed as a codec format for such digital microscopic image data.
However, also in this case, since a plurality of JPEG data should be obtained for a single specimen, a large capacity is used for storing and managing the data. Accordingly, an amount of data should be reduced.
For example, a compression method for a plurality of focus plane images using interframe encoding in which differences between adjacent frames are obtained has been proposed. Furthermore, a method for determining a focus plane serving as a reference and performing compression using blur compensating prediction utilizing a blur change obtained in accordance with an optical parameter and a Z coordinate displacement from the reference focus plane has been proposed (refer to Japanese Unexamined Patent Application Publication No. 2007-11977).
Here, in a system using the virtual microscope described above, a portion of microscopic image data which has been stored is displayed as an observation image. In this case, a quick response (display) should be performed in response to specifying of a position and a size of the portion to be displayed.